Suction-blower device



Patented June 24, 1947 sperren-BLOWER Davies.

i John P; Jason, Chicago, Ill., assignor to Breuer Electric Mfg. Co., Chicago, Ill., a corporation v of Illinois Application December 11, 1943, sei-iai No. 513,890 i 1 claim. (ol. 23o- 117) Thisr inventiony relates to improvements Ain a combined blower and suction device, that isya unit which is adapted and readily convertible for use as a blower, sprayer or vacuum cleaner.

In general `such suction-blower units `comprise amotor housed in a suitable casing having communication-therethrough to the atmosphere, a fan secured 4to the motor shaft and enclosed in a fan casing, the two casings being secured together, and an intermediate partition or motor casing and closure, the partition being provided with an annular boss or hub seating a motor shaft bearing.

In operation of the device as a suction cleaner, which entails constriction of the air stream entering the fan casing suction inlet, a condition of subfatmospheric pressure is caused to exist in the `fan casing. A tendency to relieve and balance this condition is brought about by arentering the motor casing with the result that atmospheric dust is moved through the motor shaft bearing in a direction from the motor to the fan with attendant gumming of bearing lubricant and undue abrasion of the bearing and shaft. Conversely when the device is operated as a blower, which entails construction of the air stream delivered from the fan casing exhaust outlet, a condition of super-atmospheric pressure is built up in the fan easing lwith a tendency to likewise relieve this condition through the motor casing. In this instance atmospheric dust will be moved along the motor shaft and the bearing in a direction from the fan to the motor, with like detrimental action.

It is therefore an object of the present inven' tion to provide means in a suction-blower device of the class described for permitting the establishment and maintenance of substantially normal atmospheric pressure along and within the bearing of the motor shaft between the motor and the fan during operation of the device either as a blower or suction cleaner, and to thereby prevent tendency for dust particles to move intov 2 in the direction of the line trating my invention.

Fig. 3 is a viewsimilar viewed inthe direction of the line 3-3 of Fig.` l.

Referring tothe drawings, the reference numeral IIJ indicates the motor casing of my suction-blower, unit, one end thereof being closed by the end closure plate II secured thereto by suitable screws as at I2. sure plate His the fan casing I3, the three parts being securedto-gether by suitable screws as at I4, the closure plate `II thus acting as a partitioning member between the motor and fan cas ings. u

'A centrifugal fan I5is secured as at I6 tolthe end ofthe motor shaft I] which extends through the closure plate Il.; The fan casing.- isvprovided with an axial suction inlet I8 havinga bayonet fixture I9 by meansof which a suitable suction hose and mouth may be attached when the device is used as a suction cleaner. The fan casing is further provided With a tangential exhaust port .20 provided with a similar bayonet iixture 2l to which may be attached a suitable dust bag when the device is employed as a suction cleaner, or a suitable hose and nozzle when employed as a blower.

The motor casing is provided with a series of peripheral apertures 22 adjacent the end plate II to provide communication with the atmosphere for cooling the motor aided by a fan, not shown, generally provided on the motor shaft adjacent the apertures. The motor casing is likewise provided with screen covered apertures at the opposed outer end, not shown, for the purpose of admitting air to cool the motor parts.

The motor end closure plate I I, in its face adjacent the fan I5, is provided with an annular seat 23 which received the relatively smaller diameter hub 24 of the fan, the face of the plate I I being counterbored to position a leather gasket or the like Washer 25, the latter being held in position by the ring'26. The opposed face of the plate II is provided with an annular boss 2l, extending in the direction of the motor, seating the Washer 28 and the shaft bearing generally indicated as 29.

For the purpose of establishing a condition of normal atmospheric pressure along the shaft Il, where it is jo-urnalled by the bearing 29, during operation of the device either as a blower or suction cleaner, and to thereby prevent ingress of atmospheric dust to the bearing either in a direction from the fan to the motor when a condition of super-atmospheric pressure exists in the fan casto that of Fig 2, but,

Mounted against the clocates with the atmosphere, through the motor casing at one end, and with the fan chamber at` the other end immediately in advanceof the bearing 29.

In operation of the device as improved in accordance with my invention, when a condition of sub-atmospheric pressure exists in the fan casing I3 tendency for air to move from the motorv casingv and along the motor shaft I1 through the'bearing 29, and thence through the seat 23 and past the Washer 25 is substantially eliminated, least resistance to atmospheric pressure being presented by the apertures 30, and thus the conditions of aii` pressure are permitted to become equalized immediately in -advance of the bearing 29 without disturbance therein. Conversely, when a condition of super-atmospheric pressure is built up in fan casing I3, such pressurepast the washer 25 and through the seat 23 and thence along the motor shaft I1 will be relieved through the bores 30 instead of through the shaft bearing 29. In this manner a condition of substantially normal atmospheric pressure will be enabled to exist in the bearing 29 and the parts thereof, and between it and the shaft I1, during all conditions of operation of the suction-blower unit, and without undue abrasion of the parts or gumming of lubricant by reason of freedom from disturbance by air and airborne contaminants. Y

I claim as my invention:

In a suction blower device of the class described. an electric motor having a casing opened at one end to the atmosphere, a plate-shaped partition secured to the open end of the motor casing and having a central opening formed therein to receive a motor shaft, a fan casing formed with a suction inlet and exhaust outlet and an open end, said fan casing being mounted on said partition and having its open end closed by same, a centrifugal fan disposed within the fan casing and secured to the end of the motor shaft on the opposite side of the partition from the motor, the cenjtralopening in said partition being formed with central opening, gasket means mounted Within an'annular recess dening an air chamber between the motor shaft and the wall dening said said central opening of the partition and disposed at opposite ends of said annular recess dening the air chamber, said partition having an unobstructed air duct passage leading from said annular recess dening the air chamber around thev shaft to exhaust within the interior of the motor casing, and an anti-friction bearing mounted in said central opening formed in said partition and adjacent the vmotor side of said annular recess to provide an auxiliary support for the motor shaft.

JOHN P. JASON.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 

